climbing nightshade vs bittersweet nightshade

climbing nightshade and bittersweet nightshade both are nouns.

Word	Noun	Adjective	Verb	Adverb
climbing nightshade	Yes	No	No	No
bittersweet nightshade	Yes	No	No	No

As nouns, climbing nightshade and bittersweet nightshade are synonyms defined as:

climbing nightshade and bittersweet nightshade: poisonous perennial Old World vine having violet flowers and oval coral-red berries; widespread weed in North America

Other synonyms of climbing nightshade include bittersweet, deadly nightshade, poisonous nightshade, Solanum dulcamara, woody nightshade.

climbing nightshade (noun)	bittersweet nightshade (noun)
poisonous perennial Old World vine having violet flowers and oval coral-red berries; widespread weed in North America	poisonous perennial Old World vine having violet flowers and oval coral-red berries; widespread weed in North America